The present invention generally relates to an apparatus and method for editing a dictionary for use in translation in a mechanical translation system.
A mechanical translation system has been proposed in Japanese Laid-Open Patent Application Nos. 63-136265 and 61-90271, for example. Japanese Laid-Open Patent Application No. 63-136265 is directed to registering a new equivalent in an object language, which is added to or substituted for an equivalent registered in the system. Japanese document 63-136265 discloses a system which is composed of specifying means for specifying a desired source word in an input sentence, output means for reading out a registered equivalent of the source word from a dictionary, input means for inputting a new equivalent, means for adding or substituting the new equivalent to or for the registered equivalent, and means for primarily using the new equivalent when translating.
Japanese Laid-Open Patent Application No. 61-90271 discloses a mechanical translation system in which a word to be translated in a sentence is specified and the contents of a dictionary corresponding to the specified word are displayed. When a desired equivalent in an object language is not included in a displayed equivalent, a desired equivalent is registered by the user. Further, a dictionary editing apparatus for use in translation has been proposed. For example, an equivalent in an object language is disassembled into an independent part and an adjunct part. The adjunct part is recorded as information about attributes of the equivalent. The independent word is processed as a corresponding equivalent.
However, the above-mentioned apparatuses are primarily oriented to declinable words (words corresponding to verb phrases). That is, a word is analyzed so that declinable information on tense, aspect, mode and structure of declinable words is automatically obtained. From this point of view, the above-mentioned apparatuses are not effective for processing of noun phrases. Particularly, there is a need to specify a portion of a noun phrase which corresponds to a main noun and inputting information on morphology, grammatical construction and meanings of the main noun.
There is a need to register a new equivalent of a word in a mechanical translation apparatus in which a word A in an original language is automatically translated into an equivalent B in an object language. When registering a new equivalent, it is necessary to register a part of speech, declension and meanings thereof together. Thus, the registering operation is troublesome.
For example, according to Japanese Laid-Open Patent Application No. 63-136265, a word in an original language is specified by the user, and an equivalent is input. It is very difficult to derive an equivalent of the word to be translated from the registered word itself since information about a part of speech or declension is lacking in the registered word itself. Thus, it is very difficult to obtain, from the registered equivalent itself, a correct order of words or correct connections of words. For these reasons, it is necessary for the user to register information about a part of speech and declension needed for translation, and information on the meanings if necessary. Such a registering procedure needs specific knowledge and thus it is extremely difficult for the general user to manually carry out a registering operation.
The above-mentioned discussion holds true for the system disclosed in Japanese Laid-Open Patent Application No. 61-90271. Specific knowledge is needed to register a new word and its equivalent together with attribute information thereon. Thus, the procedure for adding a new equivalent or revising the existing equivalent in the dictionary is very troublesome.
The aforementioned conventional dictionary editing apparatus for use in translation can reduce the word load for a user during registering of an equivalent in an object language. However, it is impossible to process a word such as a noun phrase having no adjunct part and process attributes of composite nouns, particularly information on their meanings.